"""
Kin CLI — kin watch <task_id> and kin ps commands.

kin watch: polling monitor, updates every 5s (like tail -f for a pipeline).
kin ps: one-shot list of all running pipelines with PID and current step.
"""

import json
import time
from datetime import datetime

from core import models


def _clear_screen() -> None:
    print('\033[2J\033[H', end='', flush=True)


def _format_elapsed(dt_iso: str) -> str:
    """Format elapsed time from SQLite CURRENT_TIMESTAMP (UTC naive, space separator)."""
    try:
        # SQLite stores "YYYY-MM-DD HH:MM:SS"; fromisoformat requires 'T' in Python < 3.11
        normalized = dt_iso.replace(' ', 'T') if ' ' in dt_iso else dt_iso
        started = datetime.fromisoformat(normalized)
        total_secs = int((datetime.utcnow() - started).total_seconds())
        if total_secs < 0:
            total_secs = 0
        hours = total_secs // 3600
        minutes = (total_secs % 3600) // 60
        secs = total_secs % 60
        if hours > 0:
            return f"{hours}h {minutes}m"
        elif minutes > 0:
            return f"{minutes}m {secs}s"
        else:
            return f"{secs}s"
    except (ValueError, TypeError):
        return "?"


def _parse_total_steps(steps) -> int | str:
    """Return total planned steps from pipeline.steps (may be list or raw JSON string)."""
    if steps is None:
        return '?'
    if isinstance(steps, list):
        return len(steps)
    # Fallback: raw JSON string (legacy or unexpected path)
    if isinstance(steps, str):
        try:
            parsed = json.loads(steps)
            if isinstance(parsed, list):
                return len(parsed)
        except (json.JSONDecodeError, ValueError):
            pass
    return '?'


def _render_watch(
    task: dict,
    pipeline: dict | None,
    log: dict | None,
    step_num: int,
    total_steps: int | str,
) -> None:
    """Render the watch screen to stdout."""
    sep = '─' * 60
    title = task['title'] or ''
    title_short = (title[:50] + '…') if len(title) > 50 else title

    print(f"kin watch {task['id']}")
    print(sep)
    print(f"Task:    {task['id']}  {title_short}")
    print(f"Status:  {task['status']}")

    if pipeline:
        pid_str = str(pipeline['pid']) if pipeline.get('pid') else '-'
        print(f"Pipeline: #{pipeline['id']}  [{pipeline['status']}]  PID: {pid_str}")
        elapsed = _format_elapsed(pipeline['created_at'])
        print(f"Elapsed: {elapsed}  |  Agents run: {step_num} / Total planned: {total_steps}")
        print()
        current = log['agent_role'] if log else 'Waiting for first agent...'
        print(f"Current agent: {current}")
    else:
        print()
        print("No pipeline started yet.")

    print(sep)

    if log and log.get('output_summary'):
        lines = (log['output_summary'] or '').splitlines()
        for line in lines[-15:]:
            print(line)
    elif pipeline:
        print("Waiting for first agent...")

    print(sep)

    terminal_statuses = ('completed', 'failed', 'cancelled')
    if pipeline and pipeline['status'] in terminal_statuses:
        print(f"[Pipeline {pipeline['status']}. Exiting.]")
    else:
        print("[Updating every 5s. Ctrl+C to stop]")


def _render_ps(rows: list[dict]) -> None:
    """Render the running pipelines table to stdout."""
    if not rows:
        print("No running pipelines.")
        print("\nUse 'kin watch <task_id>' to monitor.")
        return

    print(f"Running pipelines: {len(rows)}\n")

    headers = ["ID", "TASK", "PROJECT", "PID", "STARTED", "AGENT", "PARENT"]
    col_widths = [len(h) for h in headers]

    formatted_rows = []
    for r in rows:
        title = r.get('title') or ''
        title_short = (title[:20] + '…') if len(title) > 20 else title
        pid_str = str(r['pid']) if r.get('pid') else '-'
        started = (_format_elapsed(r['created_at']) + ' ago') if r.get('created_at') else '-'
        agent = r.get('current_agent') or '-'
        parent = str(r['parent_pipeline_id']) if r.get('parent_pipeline_id') else '-'
        row = [f"#{r['id']}", title_short, r.get('project_name') or '-',
               pid_str, started, agent, parent]
        formatted_rows.append(row)
        for i, cell in enumerate(row):
            col_widths[i] = max(col_widths[i], len(str(cell)))

    fmt = '  '.join(f'{{:<{w}}}' for w in col_widths)
    print(fmt.format(*headers))
    print(fmt.format(*('-' * w for w in col_widths)))
    for row in formatted_rows:
        print(fmt.format(*row))

    print("\nUse 'kin watch <task_id>' to monitor.")


def cmd_watch(conn, task_id: str) -> None:
    """Polling monitor for a task. Updates every 5s. Exits on terminal pipeline state."""
    import sqlite3
    task = models.get_task(conn, task_id)
    if not task:
        print(f"Task '{task_id}' not found.")
        return

    try:
        while True:
            _clear_screen()
            pipeline = models.get_pipeline_for_watch(conn, task_id)

            if pipeline:
                log = models.get_current_agent_log(conn, task_id, pipeline['created_at'])
                step_num = conn.execute(
                    'SELECT COUNT(*) FROM agent_logs WHERE task_id = ? AND created_at >= ?',
                    (task_id, pipeline['created_at']),
                ).fetchone()[0]
                total = _parse_total_steps(pipeline.get('steps'))
            else:
                log, step_num, total = None, 0, '?'

            _render_watch(task, pipeline, log, step_num, total)

            if pipeline and pipeline['status'] in ('completed', 'failed', 'cancelled'):
                break

            time.sleep(5)

    except KeyboardInterrupt:
        print('\nExiting watch mode.')


def cmd_ps(conn) -> None:
    """One-shot list of all running pipelines."""
    rows = models.get_all_running_pipelines(conn)
    _render_ps(rows)